This relates generally to imaging systems and, more particularly, to imaging systems with plasmonic color filters.
Opto-fluidic sensors have been developed that can be used to generate images of samples such as cells and other biological specimens. In conventional systems, the samples are suspended in a fluid. The fluid flows over a set of image sensor pixels each having a photodiode. The image sensor pixels may be associated with an image sensor pixel array. As the fluid flows through the channel, image data from the pixels is acquired and processed to form images of the sample.
A light source is sometimes provided, that illuminates the samples. In some situations the light source is configured to excite fluorescent material in the sample. The image sensor is often used to capture images of the fluorescent light. However, it can be difficult to prevent the excitation light from the light source from contaminating fluorescence image signals without providing thick color filter layers. Color filter layers of this type can increase the distance from the sample to the photodiodes in the sensor, which can undesirably affect the optical performance of the sensor. For example, this type of large distance can allow relatively large pixel-to-pixel cross talk.
It would therefore be desirable to provide imaging systems with improved color filters for microfluidic systems.